Bomb sway brace



Aug. 6, 1935. M. a. CRAWFORD BOMB SWAY BRACE Filed Jan. 16, 1934 2Sheets-Sheet l SYWWYIM Aug. 6, 1935. M. B. CRAWFORD BOMB SWAY BRACEFiled Jan. 16. 1934 2 Sheets-Sheet 2 Patented Aug. 6, 1935 PATENT OFFICEBOMB SWAY BRACE Marion B. Crawford,

Seattle, Wash., assignor to Boeing Airplane Company, Seattle,

Wasln, a

corporation of Washington Application January 16, 1934, Serial No.706,843 19 Claims. (01. 244-1) Bombing airplanes customarily carry bombsbeneath the wing or fuselage, where, with their releasable securingmeans and braces ordinarily fixed in position to prevent them fromswaying from side to side, they constitute a drag upon the airplane, andeven after the bombs have been released the sway braces, stillprojecting from, the streamlined contour, produce a very considerabledrag. After the bombs have been released it is of the utmost importancethat the bomber be able to get away as rapidly as possible, for it isonly by its speed that it can hope to escape enemy fighter planes. It ishighly desirable, therefore, that all such projecting parts, especiallythe sway braces which produce drag, be withdrawn within the streamlinedcontour, or in some manner that the streamlined contour be restored,following the release of the bombs. Since the pilot has his hands -i'ullat such time in maneuvering his; plane and in watching for enemy pursuitships, it is also desirable that no burden be placed on the pilot orother members of the crew of the bomber, who are likewise busy, to thinkand act to restore this streamlined contour, and it is thereforedesirablethat such means for restoring the streamlined shape beautomatically operable.

My invention has the accomplishment of the above aims as its principalobject. It is also an object in instances where an airplane is equippedto carry a number of bombs that each of the means for restoring thestreamlined shape be operable independently of all others, so that ifonly a portion of the bombs are released the brace members and the likewhich engaged the bombs which were released can be withdrawn into thestreamlined shape, and the latter be restored and drag eliminated orlessened that much.

plane is equipped for supporting a plurality of bombs, to provide suchbrace means which are urged into engagement each with its respectivebomb, and retractable independently of all others,

to provide means whereby all such means may be relaxed simultaneously tofacilitate the securement of the bombs, and further, which may besimultaneously brought into operation so that each means will then braceits respective bomb, regardless of variations in their size.

It is a further object to provide a bomb sway brace means for one or aplurality of bombs, which shall be simple in construction and easilyoperable, self-conforming to difl'erent sizes oi. bombs, and one whichcan be readily incorporated into an airplane structure, lying within thestreamlined shape of the structure except as the brace means areprojected into the wind stream to brace the bombs supported outside thestreamlined structure.

Other objects will be ascertained from the attached drawings and fromthis specification, especially such as relate to structural details.

My invention comprises the novel sway brace means, both of eachindividual unit and of the plurality of units as a whole, and the novelconstruction and assemblage of parts to the end of accomplishing theabove and other objects.

In the accompanying drawings I have shown my invention embodied in atypical form, as now preferred by me. 1

Figure 1 is a top plan view of the device as a whole, the operatinghandle being omitted, and with parts shown in the relaxed position,ready for the securement of bombs.

Figure 2 is a view similar to Figure 1, but showing parts in theoperative position.

Figure 3 is a side elevation, with parts broken away, of the device as awhole, showing parts in the operative position.

Figure 4 is a transverse section on the line 4-4 of Figure 3, and Figure5 is a similar section on the line 5-5 of Figure 3. a

Figure 6 is an underside view in perspective of the center section. of atypical bomber, showing my device incorporated therein.

In Figure 6 the bombs B2, B3, I34 and B5 are shown supported beneath thecenter section of the wing 9. It will be understood, of course, thatthey might be supported from the fuselage 90, or from any suitable partof the airplane structure, which part would usually be streamlined. Inany instance they are supported outstream. The manner of theirsecurement is immaterialv in so far as my invention is concerned, and isillustrated only diagrammatically at Si in Figure 3. In this same figurethe skin 92 of the wing 9 is illustrated in section. It is a furtherobject, especially where the air- To prevent the bombs from swaying fromside to side I employ brace members each comprising a plate I pivoted atl0 within the airplane structure on an axis extending longitudinally ofthe airplane, whereby the braces will swing transversely. Each plate maybe apertured for lightness, .but in effect it constitutes a flat surfacedirectly opposed to the wind stream, which causes an appreciable amountof drag. To eliminate this drag I provide means whereby as each bomb isreleased the pair of brace members, one engaging each side of such bomb,is withdrawn within the airfoil or streamlined shape, and to this end Iprovide on each plate I an arm II which is pivotally connected at i2 toa clip 22 which is mounted and slidable upon a rod 2. Two such rods areemployed, which to distinguish them are designated 2 and 2', and theseare slidable lengthwise in guides 20 supported from the airplanestructure. As a convenient means of supporting the rods and the bracemembers I I side of the streamlined contour in the wind provide achannel structure 3, the pivots Ill being supported in the flanges ofthe channel, and the guides 20 being mounted on the web thereof. Thischannel 2 may conveniently be secured in any suitable manner, as by therivets 2i, which connect its outspread flanges to the skin 82 of thewing or fuselage. Connection is. established from each of the members Ito a rod 2 or 2' by means of the clips or arms 22 heretofore referredto, these clips being freely slidable along the respective rods. Thereason for employing two rods is that the two brace memhers I of eachpair swing oppositely on their pivots toward each other, and engage onopposite sides of a bomb, hence by movement of one of the clips 22 inone direction and the oth'er clip in the opposite direction the twobrace members of a pair can be moved toward each other and through theaperture 93 in the wing skin through which they project, into thestreamlined shape. They may be formed to substantially close thisaperture when retracted, as seen in the middle pair of Figure 3, wherebythey not only lessen or eliminate the drag caused when they project, butsubstantially restore the streamlined shape.

It would be possible to provide a rod such as 2 breach of the bracemembers I, but it is unnecessary to do so, and it eliminates weight toprovide only the two of them, the rod 2 and the rod 2', and each suchrod may be caused to urge each one of the brace members I which isconnected thereto against the side of a bomb by such means as anextension coil spring 4, one end of which is connected cated at ",andthe other end of which is con nected to the clip 22, as indicated at H.1 By moving the point 40 away from the point ll, the spring is tensionedand the brace member connected the to is caused to be drawn against theside of the bomb. If, however, the bomb is released the extended springwill act to throw the brace member I upward within the wing. If, on theother hand, the point 40 is moved toward the point ll, and the movementof the latter point and of the associated brace member is stopped byreason of the engagement of the pivot l2 at the end of an arcuate slot23 in the channel member 4, then the tendency to withdraw the bracemembers is relieved, and the springs are relaxed, whereupon a bomb mayreadily be se-' cured in place beneath the wing. Notwithstanding thatthe device may be so operated that all the brace members are relaxedsimultaneously, it will be clear that each individual pair of bracemembers may be withdrawn independently of all other pairs, immediatelyupon release of the bomb with whichthey are associated, so long as itssprings remain extended.

In order to accomplish such relaxation and extension of the severalsprings, means areprovided to move the rods 2 and 2' longitudinally, andto this end there may be formed upon each of them a series of rack teeth25 (see Figure 1) and these portions of the rods may be guided in aguide 26, whereon is journaled a rack pinion 21, with which isassociated a handle 28, and a spring pawl 29 is provided, engageablewith the pinion 21 and operable to hold the springs extended,- or whenreleased from the pinion,-to permit the springs to relax as they drawthe rods from the position of Figure 2 to that of Figure 1.

The device is supported, as described, preferably within the streamlinedform of the airplane structure, though the manner of its support is imtothe rod, as indi-' material. The channel member 8 in effect formspurposes of supporting the braces I. The springs are relaxed, the bombsare secured in place, and the springs are then extended by rotating thehandle 28, the pawl 29 being engaged with the pinion 21. Now as eachbomb is released the extended spring associated with the correspondingbraces causes these braces tobe withdrawn, yet the force of all othersprings is retained 'unchanged so long as the bomb associated therewithremains in place.

It may be pointed out here that the physical withdrawal of the braces isonly one of a number of ways in which the drag of such members can belessened. They might be turned into a position where their drag islessened without any or without entire withdrawal thereof, or thestreamlined structure may be altered by the projection of devices suchas fairing means to include the braces, after the bomb has beenreleased. I do not desire to be limited merely towithdrawal of thebraces, whether partial or complete, other than as required by theappended claims. Purthermore,'the movement of the braces might beotherwise than a pivotal movement, and this is within the intended scopeof my invention. The

particular means for operating the braces might by the brace means orother means associated with the. bomb,.whether. by movement thereof intoa position of less drag, or by their complete withdrawal or shielding.

What I claim as my invention is:

1. In combination with an airplane structure whereon are means toreleasably support bombs, means separate from the bomb supporting meansto brace such bombs, said brace means projecting, when in operativeposition, into the wind stream, and means operable following release ofits bomb to lessen the drag of said brace means.

2. In combination with an airplane structure, means to brace bombs,releasably supported thereon, against swaying, said means projectingfrom the airplane structure into the wind stream, and meansautomatically operable upon release of a bomb to lessen the drag of saidbrace means.

3. In combination with an airplane structure,.

on, against swaying, said means, when in operative position projectingfrom the airplane structure into the wind stream, and meansautomatically operable upon release of a bomb to move said brace meansfrom such operative position into a position wherein its drag islessened.

4. Incombinatlon with a streamlined structure, means to brace bombswhich are releasably supported thereon, against swaying, said meansprojecting from the structure into the wind stream, and meansautomatically operable upon release of a bomb to withdraw said bracemeans to restore the streamline thereof.

5. In combination with an airplane structure, a pair of members mountedthereon and in operative position cooperatively engageable with a, bombreleasably mounted thereon'to brace the bomb against swaying, andprojecting, when in such operative position, into the wind stream, andmeans operable following release of such bomb to lessen the drag causedby such members.

6. In combination with an airplane structure, a pair of brace memberspivotally mounted at points spaced transverselyof the airplanestructure, on axes extending longitudinally, and spring means normallyacting upon said brace members to. swing the latter into the airplanestructure, and holding them, when a bomb is disposed therebetween,against opposite sides of the bomb.

7. In combination with an airplane structure, a pair of brace memberspivotally mounted at points spaced transversely of the airplanestructure, on axes extending longitudinally, spring means normallyacting upon said brace members to swing the latter -into the airplanestructure,

and holding them, when a bomb is disposed therebetween, against oppositesides of the bomb, and means to relax said spring means to facilitatesecurement of the bomb in such position.

8. In combination with an airplane structure, a plurality of means eachoperable to brace its respective one of a plurality of bombs which areby other means releasably supported from theairplanestructure, saidbrace means projecting, when in operative position, into the windstream, and means operable following release of any given bomb to lessenthe drag of the corresponding brace means.

9. In combination with an airplane structure, a plurality of means eachoperable to brace its respective one of a plurality of bombs which arereleasably supported from the airplane structure, said means projecting,when in operative position, into the wind stream, and meansautomatically operable upon release of a bomb, to move the correspondingbrace means into a position wherein its drag is lessened.

10. In combination with an apertured streamlined structure, a pluralityof means each operable to brace its respective one of a plurality oibombs which are releasably supported from said structure, said means, insuch operative position, projecting through the apertures in thestructure into the wind stream, and means operable upon release of anybomb to move the corresponding brace means into the structure, tosubstantially close the corresponding aperture and restore thestreamline forrnof the structure.

11. In combination with an airplane structure, a plurality of means eachengageable with its respective one of a plurality of bombs releasablysupported from the airplane structure, to brace such bomb againstswaying, and means acting upon each of said brace means to cause thelatter to conform automatically and individually to various sizes ofbombs, said means being further and automatically operable,independently of the other brace means, and following release of itscorresponding bomb, to lessen the drag caused by the projection of suchbracing means into the air stream.

12. In combination with an airplane structure, a plurality of means eachengageable with its respective one of a plurality of bombs releasablysupported from the airplane structure, to brace such bomb againstswaying, spring means urging each such brace means against itsrespective bomb, and means to relax the spring means of all brace meanssimultaneously, to facilitate securement of the bombs.

13. In combination with an airplane structure, a plurality of pairs ofbrace members pivotally mounted upon and in operativeposition'projecting from the airplane structure, spring means actingupon said members when projected to urge the two members of each pairinto engagement with opposite sides of its respective one of a pluralityof bombs releasably supported from,

3 the airplane structure. and further operable, independently of allother pairs of brace members, to retract its associated brace memberswithin the airplane structure.

14. In combination with an airplane structure, a plurality of pairs ofbrace members pivotally mounted upon and in operative positionprojecting from the airplane structure, spring means acting uponsaid'members when projected to urge the two members of each pair intoengagement with opposite sides of its respective one of a pinrality ofbombs releasably supported from the airplane structure, and furtheroperable, independently of all other pairs of brace members, to retractits associated brace members within the airplane structure, and means tosimultaneously relax the spring means of all pairs of brace members, tofacilitate securement of the bombs to the airplane structure.

15. In combination with an apertured streamlined airplane structure, aplurality of pairs of brace members of generally flat shape disposedtransversely of the air stream, and pivotally mounted upon the airplanestructure upon longitudinally extending axes, to swing through theapertures into the wind stream, thereby to engage the two members oi.each pair with opposite sides of its respective one of a plurality ofbombs releasably supported from the airplane structure, and in the windstream, and meansoperable following release of any bomb to withdraw itsbrace members, independently of all other brace members through theirrespective apertures, thereby to restore this portion of the streamlineform of the airplane structur 16. In combination with a streamlinedairplanestructure whereon a bomb is releasably supported in the windstream, means projecting from the streamline form and engageable withsuch bomb, while thus supported and means operable following the releaseof such bomb to restore the streamline form of the airplane structure.

17. In combination with a streamlined airplane structure whereon a bombis releasably supported in the wind stream, means projecting from thestreamline form and engageable with such bomb, while thus supported, andmeans operable automatically by release of such bomb to move saidprojecting means into, a position wherein its drag is lessened.

18. In combination with an airplane structure, and with means thereon tosuspend a bomb freely beneath the airplane structure, for releasetherefrom, means engageable with such a bomb to brace the bomb againstswaying, and means acting upon said brace means to cause the latter toconform automatically to any one of various sizes of bombs, said meansbeing further and automatically operative, following the release of thecorresponding bomb, to lessen the drag caused by the projection of thebracing means into the air stream.

19. In combination with an airplane structure,

and with means thereon to suspend a bomb freely beneath the airplanestructure, for release therefrom, means engageable with such a bomb tobrace the bomb against swaying, means acting upon said brace means tocause the latter to conform automatically to any one of various sizes ofbombs, and means to render inoperative the bracing means, at will.

MARION B. CRAWFORD.

